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记一次虚机强制断电 K8s 集群 etcd pod 挂掉快照丢失(没有备份)问题处理

山河已无恙 2023-03-28 原文

写在前面

  • 不小心拔错电源了，虚机强制关机，开机后集群死掉了
  • 记录下解决方案
  • 断电导致etcd 快照数据丢失，没有备份.基本上是没办法处理
  • 可以找专业的 DBA来处理数据看有没有可能恢复
  • 这篇博文的解决办法是删除了 etcd 数据目录中的部分文件。
  • 集群可以启动，但是 部署的环境数据都丢失了，包括CNI, 集群自带的 DNS 组件也丢了。
  • 理解不足小伙伴帮忙指正
  • <font color=red>不管是生产还是测试，如果没做UPS电源， k8s集群 ETCD 一定要备份，ETCD 一定要备份，ETCD 一定要备份 ，重要的话说三遍。</font>
我所渴求的，無非是將心中脫穎語出的本性付諸生活，為何竟如此艱難呢 ------赫尔曼·黑塞《德米安》

当前集群的状态

┌──[root@vms81.liruilongs.github.io]-[~] └─$kubectl get nodes The connection to the server 192.168.26.81:6443 was refused - did you specify the right host or port? 重启 docke 和 kubelet 尝试启动

┌──[root@vms81.liruilongs.github.io]-[~] └─$systemctl restart docker ┌──[root@vms81.liruilongs.github.io]-[~] └─$systemctl restart kubelet.service 还是不行，查看下 maser 节点的 kubelet 日志信息

┌──[root@vms81.liruilongs.github.io]-[~] └─$journalctl -u kubelet.service -f 1月 19 09:32:06 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:06.703418 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 1月 19 09:32:06 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:06.804201 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 1月 19 09:32:06 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:06.905156 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 1月 19 09:32:07 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:07.005487 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 1月 19 09:32:07 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:07.105648 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 1月 19 09:32:07 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:07.186066 11344 controller.go:144] failed to ensure lease exists, will retry in 7s, error: Get "https://192.168.26.81:6443/apis/coordination.k8s.io/v1/namespaces/kube-node-lease/leases/vms81.liruilongs.github.io?timeout=10s": dial tcp 192.168.26.81:6443: connect: connection refused 1月 19 09:32:07 vms81.liruilongs.github.io kubelet[11344]: E0119 09:32:07.205785 11344 kubelet.go:2407] "Error getting node" err="node \"vms81.liruilongs.github.io\" not found" 利用 docker 查看下当前存在的 pod 信息

┌──[root@vms81.liruilongs.github.io]-[~] └─$docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES d9d6471ce936 b51ddc1014b0 "kube-scheduler --au…" 17 minutes ago Up 17 minutes k8s_kube-scheduler_kube-scheduler-vms81.liruilongs.github.io_kube-system_e1b874bfdef201d69db10b200b8f47d5_14 010c1b8c30c6 5425bcbd23c5 "kube-controller-man…" 17 minutes ago Up 17 minutes k8s_kube-controller-manager_kube-controller-manager-vms81.liruilongs.github.io_kube-system_49b7654103f80170bfe29d034f806256_15 7e215924a1dd registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 18 minutes ago Up About a minute k8s_POD_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_7 f557435d150e registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 18 minutes ago Up 18 minutes k8s_POD_kube-scheduler-vms81.liruilongs.github.io_kube-system_e1b874bfdef201d69db10b200b8f47d5_7 5deaffbc555a registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 18 minutes ago Up 18 minutes k8s_POD_kube-controller-manager-vms81.liruilongs.github.io_kube-system_49b7654103f80170bfe29d034f806256_7 a418c2ce33f2 registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 18 minutes ago Up 18 minutes k8s_POD_kube-apiserver-vms81.liruilongs.github.io_kube-system_a35cb37b6c90c72f607936b33161eefe_6 etcd 没有启动， apiservice 也没有启动。

┌──[root@vms81.liruilongs.github.io]-[~] └─$docker ps -a | grep etcd b5e18722315b 004811815584 "etcd --advertise-cl…" 5 minutes ago Exited (2) About a minute ago k8s_etcd_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_19 7e215924a1dd registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 21 minutes ago Up 4 minutes k8s_POD_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_7 尝试重新启动 etcd

┌──[root@vms81.liruilongs.github.io]-[~] └─$docker restart b5e18722315b b5e18722315b 查看启动状态

┌──[root@vms81.liruilongs.github.io]-[~] └─$docker ps -a | grep etcd b5e18722315b 004811815584 "etcd --advertise-cl…" 5 minutes ago Exited (2) About a minute ago k8s_etcd_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_19 7e215924a1dd registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 21 minutes ago Up 4 minutes k8s_POD_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_7 ┌──[root@vms81.liruilongs.github.io]-[~] └─$docker logs b5e18722315b 看一下 etcd 对应的日志

┌──[root@vms81.liruilongs.github.io]-[~] └─$docker logs 8a53cbc545e4 .................................................. {"level":"info","ts":"2023-01-19T01:34:24.332Z","caller":"etcdserver/backend.go:81","msg":"opened backend db","path":"/var/lib/etcd/member/snap/db","took":"5.557212ms"} {"level":"warn","ts":"2023-01-19T01:34:24.332Z","caller":"wal/util.go:90","msg":"ignored file in WAL directory","path":"0000000000000014-0000000000185aba.wal.broken"} {"level":"info","ts":"2023-01-19T01:34:24.770Z","caller":"etcdserver/server.go:508","msg":"recovered v2 store from snapshot","snapshot-index":26912747,"snapshot-size":"42 kB"} {"level":"warn","ts":"2023-01-19T01:34:24.771Z","caller":"snap/db.go:88","msg":"failed to find [SNAPSHOT-INDEX].snap.db","snapshot-index":26912747,"snapshot-file-path":"/var/lib/etcd/member/snap/00000000019aa7eb.snap.db","error":"snap: snapshot file doesn't exist"} {"level":"panic","ts":"2023-01-19T01:43:31.738Z","caller":"etcdserver/server.go:515","msg":"failed to recover v3 backend from snapshot","error":"failed to find database snapshot file (snap: snapshot file doesn't exist)","stacktrace":"go.etcd.io/etcd/server/v3/etcdserver.NewServer\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdserver/server.go:515\ngo.etcd.io/etcd/server/v3/embed.StartEtcd\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/embed/etcd.go:244\ngo.etcd.io/etcd/server/v3/etcdmain.startEtcd\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/etcd.go:227\ngo.etcd.io/etcd/server/v3/etcdmain.startEtcdOrProxyV2\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/etcd.go:122\ngo.etcd.io/etcd/server/v3/etcdmain.Main\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/main.go:40\nmain.main\n\t/tmp/etcd-release-3.5.0/etcd/release/etcd/server/main.go:32\nruntime.main\n\t/home/remote/sbatsche/.gvm/gos/go1.16.3/src/runtime/proc.go:225"} panic: failed to recover v3 backend from snapshot goroutine 1 [running]: go.uber.org/zap/zapcore.(*CheckedEntry).Write(0xc000114600, 0xc000588240, 0x1, 0x1) /home/remote/sbatsche/.gvm/pkgsets/go1.16.3/global/pkg/mod/go.uber.org/zap@v1.17.0/zapcore/entry.go:234 +0x58d go.uber.org/zap.(*Logger).Panic(0xc000080960, 0x122e2fc, 0x2a, 0xc000588240, 0x1, 0x1) /home/remote/sbatsche/.gvm/pkgsets/go1.16.3/global/pkg/mod/go.uber.org/zap@v1.17.0/logger.go:227 +0x85 go.etcd.io/etcd/server/v3/etcdserver.NewServer(0x7ffe54af1e25, 0x1a, 0x0, 0x0, 0x0, 0x0, 0xc0004cf830, 0x1, 0x1, 0xc0004cfa70, ...) /tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdserver/server.go:515 +0x1656 go.etcd.io/etcd/server/v3/embed.StartEtcd(0xc0000ee000, 0xc0000ee600, 0x0, 0x0) /tmp/etcd-release-3.5.0/etcd/release/etcd/server/embed/etcd.go:244 +0xef8 go.etcd.io/etcd/server/v3/etcdmain.startEtcd(0xc0000ee000, 0x1202a6f, 0x6, 0xc000428401, 0x2) /tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/etcd.go:227 +0x32 go.etcd.io/etcd/server/v3/etcdmain.startEtcdOrProxyV2(0xc00003a120, 0x12, 0x12) /tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/etcd.go:122 +0x257a go.etcd.io/etcd/server/v3/etcdmain.Main(0xc00003a120, 0x12, 0x12) /tmp/etcd-release-3.5.0/etcd/release/etcd/server/etcdmain/main.go:40 +0x11f main.main() /tmp/etcd-release-3.5.0/etcd/release/etcd/server/main.go:32 +0x45 "msg":"failed to recover v3 backend from snapshot","error":"failed to find database snapshot file (snap: snapshot file doesn't exist)","

"msg": "从快照恢复v3后台失败", "error": "未能找到数据库快照文件（snap: 快照文件不存在）","

断电照成数据文件损坏了，它希望从快照中恢复，但是没有快照。

额，这里没有备份，所以基本上是没有办法修复了。只能通过 kubeadm 重置集群了。

一些补救措施

如果说你希望通过一些其他的方式来启动集群，来获取一些当前集群的配置信息，下面的方式可以尝试，但是我的集群使用了下面的方法，所有的 pods 数据都丢失了，没办法最后重置集群了。

<font color=red>如果你想使用下面的方式，一定要备份删除的 etcd 数据文件</font>

etcd 在 master 是一个静态 pod ，所以我们看下 yaml 文件，配置的数据文件中什么位置

┌──[root@vms81.liruilongs.github.io]-[~] └─$cd /etc/kubernetes/manifests/ ┌──[root@vms81.liruilongs.github.io]-[/etc/kubernetes/manifests] └─$ls etcd.yaml kube-apiserver.yaml kube-controller-manager.yaml kube-scheduler.yaml - --data-dir=/var/lib/etcd

┌──[root@vms81.liruilongs.github.io]-[/etc/kubernetes/manifests] └─$cat etcd.yaml | grep -e "--" - --advertise-client-urls=https://192.168.26.81:2379 - --cert-file=/etc/kubernetes/pki/etcd/server.crt - --client-cert-auth=true - --data-dir=/var/lib/etcd - --initial-advertise-peer-urls=https://192.168.26.81:2380 - --initial-cluster=vms81.liruilongs.github.io=https://192.168.26.81:2380 - --key-file=/etc/kubernetes/pki/etcd/server.key - --listen-client-urls=https://127.0.0.1:2379,https://192.168.26.81:2379 - --listen-metrics-urls=http://127.0.0.1:2381 - --listen-peer-urls=https://192.168.26.81:2380 - --name=vms81.liruilongs.github.io - --peer-cert-file=/etc/kubernetes/pki/etcd/peer.crt - --peer-client-cert-auth=true - --peer-key-file=/etc/kubernetes/pki/etcd/peer.key - --peer-trusted-ca-file=/etc/kubernetes/pki/etcd/ca.crt - --snapshot-count=10000 - --trusted-ca-file=/etc/kubernetes/pki/etcd/ca.crt 对应的数据文件，可以尝试对数据文件进行修复，如果希望集群可以快速启动，可以

┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd/member] └─$tree . ├── snap │   ├── 0000000000000058-00000000019a0ba7.snap │   ├── 0000000000000058-00000000019a32b8.snap │   ├── 0000000000000058-00000000019a59c9.snap │   ├── 0000000000000058-00000000019a80da.snap │   ├── 0000000000000058-00000000019aa7eb.snap │   └── db └── wal ├── 0000000000000014-0000000000185aba.wal.broken ├── 0000000000000142-0000000001963c0e.wal ├── 0000000000000143-0000000001977bbe.wal ├── 0000000000000144-0000000001986aa6.wal ├── 0000000000000145-0000000001995ef6.wal ├── 0000000000000146-00000000019a544d.wal └── 1.tmp 2 directories, 13 files 备份一下数据文件

┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ls member ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$tar -cvf member.tar member/ member/ member/snap/ member/snap/db member/snap/0000000000000058-00000000019a0ba7.snap member/snap/0000000000000058-00000000019a32b8.snap member/snap/0000000000000058-00000000019a59c9.snap member/snap/0000000000000058-00000000019a80da.snap member/snap/0000000000000058-00000000019aa7eb.snap member/wal/ member/wal/0000000000000142-0000000001963c0e.wal member/wal/0000000000000144-0000000001986aa6.wal member/wal/0000000000000014-0000000000185aba.wal.broken member/wal/0000000000000145-0000000001995ef6.wal member/wal/0000000000000146-00000000019a544d.wal member/wal/1.tmp member/wal/0000000000000143-0000000001977bbe.wal ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ls member member.tar ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$mv member.tar /tmp/ ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$rm -rf member/snap/*.snap ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$rm -rf member/wal/*.wal ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ 重新启动 docker 对应的镜像，或者重新启动 kubectl。

┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$docker ps -a | grep etcd a3b97cb34d9b 004811815584 "etcd --advertise-cl…" 2 minutes ago Exited (2) 2 minutes ago k8s_etcd_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_45 7e215924a1dd registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 3 hours ago Up 2 hours k8s_POD_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_7 ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$docker start a3b97cb34d9b a3b97cb34d9b ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$docker ps -a | grep etcd e1fc068247af 004811815584 "etcd --advertise-cl…" 3 seconds ago Up 2 seconds k8s_etcd_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_46 a3b97cb34d9b 004811815584 "etcd --advertise-cl…" 3 minutes ago Exited (2) 3 seconds ago k8s_etcd_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_45 7e215924a1dd registry.aliyuncs.com/google_containers/pause:3.5 "/pause" 3 hours ago Up 2 hours k8s_POD_etcd-vms81.liruilongs.github.io_kube-system_1502584f9ab841720212d4341d723ba2_7 ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ 查看 Node 状态

┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$kubectl get nodes NAME STATUS ROLES AGE VERSION vms155.liruilongs.github.io Ready <none> 76s v1.22.2 vms81.liruilongs.github.io Ready <none> 76s v1.22.2 vms82.liruilongs.github.io Ready <none> 76s v1.22.2 vms83.liruilongs.github.io Ready <none> 76s v1.22.2 ┌──[root@vms81.liruilongs.github.io]-[/var/lib/etcd] └─$ 查看集群当前所有的 Pod 。

┌──[root@vms81.liruilongs.github.io]-[~/ansible/kubevirt] └─$kubectl get pods -A NAME READY STATUS RESTARTS AGE etcd-vms81.liruilongs.github.io 1/1 Running 48 (3h35m ago) 3h53m kube-apiserver-vms81.liruilongs.github.io 1/1 Running 48 (3h35m ago) 3h51m kube-controller-manager-vms81.liruilongs.github.io 1/1 Running 17 (3h35m ago) 3h51m kube-scheduler-vms81.liruilongs.github.io 1/1 Running 16 (3h35m ago) 3h52m 网络相关的 pod 都不在了,而且 k8s 的 dns 组件也没有起来， 这里需要 重新配置网络，有点麻烦，正常情况下如果， 网络相关的组件没有起来， 所有节点应该都是未就绪状态。感觉有点妖。。。时间关系，我需要集群来做实验，所以通过 kubeadm重置了

┌──[root@vms81.liruilongs.github.io]-[~/ansible] └─$kubectl apply -f calico.yaml

博文参考

https://github.com/etcd-io/etcd/issues/11949

虚机etcdquotliruilongsgithubbashdockerOpenStack云计算指尖人生

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